Security system employing a hall effect sensor

摘要

A monitoring system includes a sensor arrangement for monitoring first and second adjacent members that are displaceable with respect to one another, The sensor includes a magnet securable to the first adjacent member and an analog magnetic transducer securable to the second adjacent member in sufficient proximity of the permanent magnet to sense a magnetic field therefrom. An analog subsystem supplies electrical power to the magnetic transducer and receives an electrical signal generated by the transducer in response to a change in the magnetic field detected by the magnetic transducer. The analog subsystem including a comparator for comparing the detected change in the magnetic field to a predefined threshold change in magnetic field and an electronic memory for storing the predefined threshold change in magnetic field.